Currently the only pure flying type Pokémon is a legendary. If you were tasked with creating a pure flying type Pokémon that isn’t legendary, what would you make?
what even is Flying
A few months ago I got asked about single-type Flying Pokémon and the final sentence of my answer was “no one planned for any of this, it doesn’t make sense, and it’s 20 years too late to do anything about it – but hey, that’s the type chart for you,” which… well, that sums it up, doesn’t it? I don’t think there’s a single thing that all Flying Pokémon have in common, not even the literal ability to fly, because Dodrio is a Flying-type (and frankly “flight” would also be a pretty generous description of what Gligar and Jumpluff do). The one single-typed Flying Pokémon we do have, Tornadus, is a sort of wind elemental, but it would be a stretch to say that wind is the unifying core of the Flying type, because a lot of Flying Pokémon like Fearow and Emolga have no wind-related flavour and can only learn wind attacks as egg moves, and now in generation VII we have Minior and Celesteela, who can’t even do that.
And… what is even allowed to be a pure Flying-type? Ordinary birds with no powers related to any other type are pretty firmly established as Normal/Flying. Flying insects are obviously Bug/Flying. Pterosaurs like Aerodactyl are Rock/Flying, because fossils. Anything based on an artificial flying object like a plane would probably fall under Steel/Flying. Even air elementals like Tornadus don’t necessarily escape because, in the alchemical tradition, beings of elemental air are sylphs, who would probably be Flying/Fairy in Pokémon. Anything based on clouds or weather probably becomes Electric/Flying or Water/Flying or even Ice/Flying. Most other flying mythical creatures probably fall under Dragon/Flying or Fairy/Flying or Electric/Flying or Fire/Flying or heaven knows what else.
well what if
what if we had a Pokémon based on a flying machine that somehow demonstrably didn’t belong in the Steel type
like a hot air ballo-wait, no, we already have one of those
well, what about Leonardo da Vinci’s ornithopter?
If it’s made of wood, it can hardly be a Steel-type; there’s an argument that maybe it should be Grass like Kartana (who’s made of paper) but there’s at least some wiggle room there. It can even evolve into, or from, something based on Leonardo’s aerial screw “helicopter.” Of course, we have to… bring it to life somehow… in some way that doesn’t make it a Ghost-, Psychic- or Fairy-type like Golurk, Claydol or Magearna. Unless we just want to, like, hand-wave it and say that ornithopters are somehow naturally occurring. Could a brilliant invention just… spontaneously come to life out of a desire to make its creator’s dreams come true? I mean, it’s bull$#!t, but in the Pokémon world it might be just bull$#!t enough to work, especially if we fudge everything with a bunch of phrases like “according to an old fable…” and “stories say…” If that’s our origin story then it would make sense that the species loves invention and creativity. Maybe they fly all around the world to try to see as much of it as possible, and take humans and landbound Pokémon up into the sky in order to give them inspiration and expand their horizons. If the screw-copter is the juvenile form, they might blow wherever the wind takes them, like Hoppip or Cottonee, and then begin voyages of exploration once they evolve and learn how to steer. You could have a whole story about how these Pokémon helped humans to discover and explore new uninhabited regions. Maybe have their “wings” and bodies be painted in a variety of different designs, as a riff on both Renaissance art and the World War I and II tradition of pilots decorating their planes with elaborate painted designs to customise them. That seems like something that could work.